19⁵/₆ - (10⁵/₆ - 7¹¹/₁₈ + 4,2 ) * 7,5 = 3
7,25 ¹/₁₂ + 2¹/₄
1) 10 ⁵/6 - 7 ¹¹/₁₈ = 65/6 - 137/18 = 65*3 -137 = 58/18 = 29/9
18
2) 29/9 : 7,25 = 29/9 : 725/100 = 29*100 = 4/9
9* 725
3) 1/12 + 2 ¹/₄ = 1/12 + 9/4 = 1+27 = 28/12 = 7/3
12
4) 4,2 : 7/3 = 42/10 : 7/3 = 42*3 = 9/5
10*7
5) 4/9 + 9/5 = 4*5 +9*9 = 20+81 = 101/45
45 45
6) 101/45 * 7,5 = 101/45 * 75/100 = 101/45 * 15/2 = 101*15 = 101 = 101/6
45*2 3*2
7) 119/6 - 101/6 = 119 - 101 = 18/6 = 3
6